Recent content by HiFiFreq

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    5f4 Super inspired build numbers check

    2L man your input is appreciated . I am changing this circuit from SS rectification back to tube rectification . I have been messing with the power supply rail , subbing in "sag" resistors to bring down my HT and came to the conclusion that a 5u4 would probably be the best solution . Your advice...
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    5f4 Super inspired build numbers check

    Filament voltages are good and right on at 6.3vac . The PT I'm using had a 5 volt winding that I used as a bucking transformer to bring my voltages down . I thought I was good with my numbers and wanted some confirmation . Still trying to figure this stuff out . Thanks mountainhick !
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    5f4 Super inspired build numbers check

    Please ... Built from my stash of stuff , organ trannies so voltages are a little high . Plate voltage for each tube is 457/455 vdc Plate current is .047/.050 ma Plate dissipation is 21.48/22.75 w . I built this with an adjustable bias supply and it is set to -44.7 This works out to 72/76...
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    Interesting find - what is this?

    The 6v6 is used as a voltage regulator maybe . I saw something like this on an old Allen Organ sitting in a thrift store once . There was only one tube in the entire organ so I let it stay at the thrift store .
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    Stereo Tube Amp Question

    FenderLover I had one like that and the two SE outputs were 7868 tubes . The single ended OTs were rather beefy for consumer parts . I still have them in my pile somewhere .
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    Stereo Tube Amp Question

    I built this stereo from this schematic with some changes and listen to it daily . Dead quiet at full volume no signal .
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    Stereo Tube Amp Question

    Sounds like a Motorola not a Magnavox . Are the SE outputs 7868 tubes ? I once received a Dynaco stereo amp that was used as an amplifier for a Schober organ in a church . I can't offer much so don't let my moniker fool you . I like HiFi stuff , a lot . I am terrible at the math and theory...
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    Check my schematic help mod / tweak please SE 6v6

    Using Rob Robinette's bias calculator I come up with 10.3 watts PD . 73.6% of max 14 watts . 6v6gt plate to cathode voltage is 284vdc . Voltage at pin 8 is 19.2vdc . 500 ohm cathode resistor . Where could/should an amplifier like this be biased ? I thought I needed to be closer to 100% .
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    Check my schematic help mod / tweak please SE 6v6

    Some progress . I should have described the tone as ragged maybe . I changed the first dropping resistor to a 5k resistor . That helped clear up the raggedness immensely and brought my screen voltage down under the plate voltage by about 10 volts . I removed the bypass cap from the second...
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    R.I.P. Alan White of Yes

    Sad ... I saw YES twice in the 80's at the Hollywood Sportatorium in South Florida . 90125 and Big Generator albums. They were fantastic! I was probably 18 or so .
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    Check my schematic help mod / tweak please SE 6v6

    Thanks for the suggestions . I will start with the power supply dropping resistor first and then the K resistor on the 6v6 will probably be the second change . I wont be able to start these changes until the weekend . I scored a variac at the thrift store yesterday and have been working on that...
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    Check my schematic help mod / tweak please SE 6v6

    It's a junk box Princeton , maybe . I punched the numbers into RobRobs bias calculator and it seems to be about 93% of PD . If I am using the calculator correctly . Also the plate voltage is lower than the screen voltage . May be because of my power rail . Do I need to drop some more voltage...
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    Check my schematic help mod / tweak please SE 6v6

    Just built this amp and would like some input please . It is a single ended 6v6gt output with 12ax7 pre and SS rectification . As it sits the tone is a little ratty sounding , harsh . Kind of a princeton amp but with different cap and resistor values . I used what was in arms reach and junk...
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    Scrounged power transformer CT question

    Thanks for your help TDPRI ! I'll start another thread on this amp .
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    Scrounged power transformer CT question

    All wired up now . Seems to be working well . PT not getting hot or emitting foul smells . Bonus , I have sound that is pretty good so far with my limited testing . I haven't wired in the 6v6 cathode resistor yet . I'm using jumper cables to switch in different values . I'd like to get some...




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